This invention relates to a method and means for feeding and discharging cylindrical cans in a printing machine. The major elements of such printers comprise infeed mechanism, loading means for placing cans on mandrels, a printing blanket wheel for transfering an image from the blanket cylinder to a container, and transfer mechanism for moving decorated cans to pins of a chain conveyor for passage through a curing and drying oven.
Infeed mechanisms heretofore have comprised a star wheel for delivering cans successively to a pocket wheel, as in U.S. Pat. No. 3,261,281; or have comprised a combination of elements, namely, a star wheel and a screw conveyor, as in U.S. Pat. No. 3,766,851. The infeed mechanism carried cans to a pocket or cradle wheel provided with pockets for holding cans in axial alignment with mandrels on a mandrel wheel. Pockets or cradles disclosed in the aforementioned patents are either retractable in radial directions or movable in axial directions to carry cans to mandrels. The mechanism shown in U.S. Pat. No. 3,016,153 employs push rods moving in axial directions to place cans on mandrels and also for transferring decorated cans from the mandrels to a pin chain conveyor. In the prior art constructions, the infeed means utilized various moving parts, and the discharge means employed double cams and complex mechanisms for transferring decorated cans to a pin chain conveyor.